Pyrolysis of dimethyl carbonate: PAH formation

•16 priority-PAH were quantified in the dimethyl carbonate pyrolysis.•The PAH distribution is influenced by the reaction temperature.•NAPH and ACNY were found in the highest concentrations.•The temperature had a direct influence on the toxic potential of the emissions.•The highest PAH and B[a]P-eq concentrations were found in soot.

The formation of the 16 polycyclic aromatic hydrocarbons (PAH), classified as priority pollutants by the Environmental Protection Agency (EPA), has been studied in the pyrolysis of dimethyl carbonate (DMC) at different reaction temperatures (1075-1475 K). PAH have been quantified by gas chromatography-mass spectrometry (GC-MS). The PAH speciation showed that C10-C16 PAH: NAPH, ACNY, PHEN, FANTH PYR, FLUO, ANTH, and some C20-C22 PAH: B[a]P, I[123-cd]P, and B[ghi]P, were present in high concentrations. The predominant PAH were NAPH and ACNY, and were found in significant concentrations in all phases analysed (gas phase, adsorbed on soot, and stuck on reactor walls). PAH were predominantly present in the gas phase, except at higher temperatures where most of the PAH were adsorbed on soot. The toxic potential, B[a]P-eq concentration, was determined according to the amount of PAH present in the different phases. The results showed that the highest B[a]P-eq concentration was found for the PAH adsorbed on soot corresponding to the experiment performed at 1375 K.